Sometimes referred to as the ‘forgotten organ’, the human microbiome comprises over 100 trillion organisms, most of which live in the gut. These friendly microorganisms are essential for maintaining digestive health and supporting general wellbeing. They help us to digest dietary fibre, protect us from infections and help to strengthen the immune system. It is important to maintain a large variety of microbiota in the gut, and upsetting this balance can cause health problems.

Alphega member Graham Phillips, of Manor Pharmacy group, says the public still has limited knowledge of digestive health issues. “In the UK, I believe the general public’s knowledge on the subject is limited compared to other European countries,” he says. “Here, the focus tends to be more on tackling obesity and weight related issues – and digestive health can play a vital role here.”

At Numark, patient services manager Lucy Morris, agrees, adding: “Many customers are not aware of the role their gut health has on their overall health and wellbeing. Community pharmacy is well placed to provide advice on lifestyle changes they can make to help improve their gut health.”

According to Dr Hamid Merchant, spokesperson for the charity Guts UK and leader in pharmacy at the University of Huddersfield, the gut is a gateway to the body. “We are what we eat,” he says. “The symbiotic relationship of our body with our gut microbiota holds many secrets to a healthy life, while dysbiosis can open doors to chronic illnesses.”

What is the microbiome?

Imagine the trillions of microorganisms that live within the human body as an ecosystem – rather like a rainforest. Just as an ecosystem relies on the natural balance of plants and insects to maintain a healthy environment for life, so the bacteria and other microorganisms in the gut work together to keep the digestive system healthy.

Containing around 100 trillion microorganisms of more than 1,000 varieties, every person’s microbiome has a unique composition. But it is thought that they all contain around 160 different types of bacteria, alongside other microbes such as viruses, yeasts, archaea and fungi.

Many customers are not aware of the role their gut health has on their overall health and wellbeing

The main function of the gut microbiome is to aid the digestive system. Without it, the body is unable to digest dietary fibre and many of the starchy components of food. Gut bacteria ferment fibre and starch to produce fatty acids, which the gut cells use as energy. The fatty acids are then converted into fats or sugars by other organs, including the liver.

Gut microbes also produce vitamins, including vitamins B and K. In addition, the molecules produced by gut bacteria can influence how we react to medicines such as statins. Gut bacteria are essential for the renewal of the gut lining. They play a vital role in the building of the immune system, encouraging the growth of immune tissue in babies’ digestive systems and influencing the actions of white blood cells. They also help to protect us from infection.

It is now believed that the gut microbiome can affect how the brain develops and also influence mood, as well as having as links to conditions like depression, Alzheimer’s and Parkinson’s disease.

Why is biodiversity important?

While we all have an individual gut microbiome makeup, a core set of functions are found in all healthy guts. Having a large variety of microorganism species (biodiversity) is important for a healthy gut environment. A loss of biodiversity causes health problems.

It is known, for instance, that antibiotics negatively affect the body’s microbiota, causing damage to healthy bacterial colonies that can result in changes to the microbiome. The diarrhoea infection caused by C.difficile often affects hospital patients who have had a strong dose of antibiotics.

Inflammatory bowel diseases such as Crohn’s and ulcerative colitis occur when the immune system attacks the gut lining. People affected by these conditions have fewer species of bacteria in their microbiome. A similar situation is seen in those affected by diabetes, liver disease and obesity.

What diet is best?

Diet has the biggest influence on the balance of our microbiome. We know that a well balanced diet, rich in fruit and vegetables, low in animal protein, fat and sugar, can have a beneficial effect. Prebiotic foods are especially important.

The most important thing is to eat a variety of different foods as our gut bacteria loves diversity

“Prebiotics are non-digestible food components that are fermented by the gut microbiome and stimulate beneficial microbial growth or increased activity,” explains Julie Thompson, information manager at Guts UK. “They are fibre – although not all fibre has prebiotic benefits. The prebiotics that have been most researched include inulin, fructo-oligosaccharides, oligofructose and galacto-oligosaccharides.”

The main food sources of fructo-oligosaccharides and inulin are onion, artichoke, chicory, garlic and wheat, while galacto-oligosaccharides can be obtained from lentils, chickpeas, beans and peas. Prebiotics are found in smaller amounts in many other vegetables, fruits and wholegrains.

“It is important to include wholegrain carbohydrates in the diet,” says Ms Thompson. “There is good evidence that these are beneficial in preventing bowel cancer. The advice for the general population is to include at least five portions of fruit and vegetables per day and to include wholegrain carbohydrates in three meals per day.”

Bahee Van de Bor, paediatric dietician and BDA spokesperson, says that people do not need to follow a special diet. “The most important thing is to eat a variety of different foods as our gut bacteria loves diversity,” she says. “Aim to eat at least five servings of fruit and vegetables a day, choose whole grains, lentils and legumes or one to two servings of fish and lean cuts of meat for protein. Fermented foods, drinks and yoghurt are the best sources of probiotics in the diet.”

Fermented foods include sourdough bread, kimchi, kombucha and sauerkraut, but it is not yet fully understood how, or indeed if, they all work. “They may – or may not – have live microbial content in the finished product,” says Ms Thompson. “Whilst these products when consumed regularly do seem to change the microbiota profile, more research is needed to elucidate their direct health benefits.”

Important advice for customers

Common symptoms of a dysbiotic gut microbiome include constipation, diarrhoea, bloating, recurring infections and allergies – although customers may not make the link. “Whilst most customers will notice when they are experiencing digestive upset, many may not know how long-term dysbiosis may impact their health,” says Kim Plaza, nutritional therapist and technical advisor at Protexin.

Dr Merchant advises pharmacy staff to look out for patients presenting persistently with symptoms such as indigestion, reflux, swallowing difficulty, flatulence, abdominal cramps, diarrhoea, constipation or blood in their stools. Patients with obesity and malnutrition may also have underlying gut health issues.

Ms Plaza has three top tips for pharmacy teams to pass on:

• Look at diet: Moving away from refined carbohydrates and sugars and increasing dietary fibre may encourage a higher diversity of bacterial species. A shift away from processed foods may also provide an opportunity for beneficial bacteria to thrive
• Use live bacteria supplements alongside antibiotics: Recommending the use of live bacteria alongside antibiotics (two hours apart) may reduce the risk of some side effects, such as diarrhoea
• Increase physical activity: Increasing numbers of studies are highlighting the difference in microbial diversity in populations of physically active individuals compared to those who are sedentary. Digestion issues such as constipation are thought to correlate with increased BMI, so this may provide a rationale for recommending increased levels of physical activity to customers.

Graham Phillips has this additional advice: “Ask detailed questions about your customer’s diet, how much exercise they take, how many hours sleep they get, what medication or nutritional supplements they are on and, of course, what symptoms they have. A healthy or unhealthy gut microbiome has a major impact on overall health.”

Mr Phillips adds that knowledge is key when discussing gut health. “Talk in detail to customers about symptoms they are facing and how different products could help,” he says. “This, together with advice on diet and lifestyle changes, could have a big impact on improving their gut health. Gut health is of particular relevance to people with auto-immune diseases as it may lessen some of the symptoms patients suffer.”

A healthy or unhealthy gut microbiome has a major impact on overall health

Jeremy Thorpe, managing director at Tillotts Pharma, a specialist in pharmaceuticals for GI health, says: “Pharmacy staff should also look out for patients who repeatedly buy remedies for diarrhoea, especially women over 60, as it may be related to microscopic colitis, a disease frequently misdiagnosed as IBS-D, but which with medical intervention is easily treated. The incidence is probably the same as for Crohn’s disease, but it is under-diagnosed. Pharmacists should be aware that microscopic colitis can be treated by stopping certain medications, including non-steroidals (NSAIDs) and proton pump inhibitors (PPIs). If they have patients experiencing frequent bouts of non-bloody watery diarrhoea, who are on these types of medication, stopping or changing medication may be all that is needed.”

The role of probiotics

The term “probiotics” is used to describe live microorganisms that can be added to the diet via food, drink or food supplements. They can improve the balance and function of gut bacteria and thus help to maintain intestinal health, but they must be taken continuously to maintain their effects. Prebiotics provide food for probiotics.

“Probiotics are live microorganisms composed of non-pathogenic bacteria and fungi,” explains Bahee Van de Bor. “One of the most widely recognised uses of probiotics is in the reduction in incidence and severity of diarrhoea. Probiotic strains such as Saccharomyces boularidii and Lactobacillus rhamnosus are supported by systematic reviews, and the ESPGHAN (European Society for Paediatric Gastroenterology) Working Group for Probiotics and Prebiotics agree that these strains can be used as an adjunct therapy for antibiotic-related diarrhoea and also for food poisoning and travellers’ diarrhoea.”

Emerging evidence is beginning to confirm the relationship between the microbiome and different body systems, such as the gut-brain axis

When it comes to probiotic supplements, the main difference between tablets, powders and probiotic drops is that they are designed for specific age groups, says Ms Van de Bor. “Drops are much easier for babies, whilst powders are good for toddlers and tablets for older children and adults. Yoghurts and liquids are another way of consuming probiotics.”

There is now wider public understanding of the role that probiotics can play in restoring some of the body’s healthy bacteria, but do they really work? “Many products on the market claim to contain millions of live cultures, but there is no regulatory procedure to ensure the product contains the bacterial levels stated or has enough bacteria to produce an effect,” says Dr Merchant. “Their efficacy is often a major concern as most of the bacteria or their active metabolites will not survive the harsh acidic conditions of the stomach and may not reach the colon intact.”

The global probiotics market is valued at almost US$49 billion according to Fortune Business Insights, and looks set to keep growing. Kim Plaza says we can expect to see more targeted supplements reaching the market. “Emerging evidence is beginning to confirm the relationship between the microbiome and different body systems, such as the gut-brain axis,” she says. “Products are being developed, targeting specific body systems. One example is the recent study in roundworms, where influencing the microbiome through a B. subtilis diet significantly prevented and reduced the aggregation of protein involved in Parkinson’s disease.”